lead and ball screws

Please forgive my noobage, I just wanted to give you guys a heads up on what I was doing and see if you have any input, sicne lead screw upgrade info the prusas is lackingI just bought a maker farm prusa i3v 12", and I am about to start calibrating this thing, but Ironically I already ordered 2 new 8mm x 1.25mm x 500mm length pitch screws for the prusa from qtech like another member on here did, because they were cheap enough that I didn't mind if they suck in my situation, the link for that is here: [www.qtecstore.com]

However I also went on robot digg and ordered a sfu 1204 ball screw at l360, that got here b4 i even finished the printer, i figured it coming from china and being so cheap it would take forever, but it took 4 days to my surprise and arrived b4 my printer is done, and qtech its been 2 weeks now.... i found its effective actual measured travel is 11.9" so for the makerfark 12" x and y axis this ball screw might be perfect as it comes with an anti backlash nut and machined ends, but z axis it does cut off a 1.6" inches which might not please some people, for 30$ that seems very fair... I have not seen a deal like that anywhere, usually these screws with zero machining on the ends and their huge 12mm dia cost that much, here they are rounded to nice 8mm ends so you can use 5 to 8 couplers. The link for that is here:
[www.robotdigg.com]

Also I have been looking on Hayden rapid order site(seriously why do all actual manufacturers not have stores besides hayden, igus and the other just have stupid quote requests that always wind up with redicules prices that make me not even ever want to ask again, i much rather no twait a day to hear somtethign is bogo expensive, i mean is it hard for them to at least put a range down, esp igus cuz they put down part number and tons of specs, but cant put downt he price? i dont get why when the product is clearly pre-made and pre-thought out and not a custom made 1 off screw you need to be getting a quote for, I am glad hayden has their rapid prototyping 24 hour shop, since thats at least somewhat more sane with prices listed and a simple way to order) at their 600mm lengths of 6mm dia lead screws with 2.5mm lead, going for 50$ for that length, and then 20$ for an antibacklash nut, I cant link the specific part so u would have to click metric and select 6 and 2.5 to see what I am talking about:
[prototypes.haydonkerk.com]

My question is such, is the hayden screw overkill esp for the price at 70$ with nut an axis not including the couplers I would need, I will def try to install the ball screw on the x or y axis to see how it goes to put a review for you guys on here. Qtech charges 15$ for a 500mm screw, robotdigg charges 30$ for 360mm ball screw, and hayden 70$, they basically double in price lol, and Iknow length are different, but I think for people with fat wallets esp the 6mm hayden screws might be right on the money since besides the 2.5mm lead, they also offer 1.25 and 6 i believe, so you have options, i just figure 2.5 is better than the slower ones, and still not so high for the Z axis or any other axis that the motors would be struggling.

But basically the Qtechs I ordered 2 of just cuz I assume the threaded rods are best replaced rather than wait for them to wear out and bend..however what I wonder is, if a lot of people have issues with the z axis and torque, if the ball screws would do better(and if its worth the z axis length sacrifice), even though people say you need a break with ball screws, I think in our setup with 2 motors it would not be an issue at all with backdriving but I might be wrong.

What do you guys think is the best solution in terms of an actual quality product... my concern is the qtech and robot digg products might be of less than amazing quality, given their price, neither state any specs about lead accuracy and straightness... so its a shot in the dark I am taking, that I figure I can at least metabolize into some data for you guys. Its amazing how rich this community is in knowledge but when it comes to lead screws info is super scarce, with most google searches leading to manufacturers that seem to deal in corporate orders and price quotes that are all but straight forward. I am glad at least a few sites are stocking some forms of screws, but like I said, their non statement of accuracy specs makes me think they aren't the same quality as the Haydon product, but the question is if it will be good enough for our purposes... I want to get the best possible accuracy out of this printer, and will also be replacing all wood with v slot extrusions for more stiffness... and i figure replacing the threaded rods and belts would also help. However if something I said makes no sense, feel free to let me know, or if I am expecting too much in general from an upgrade to lead or ball screws on these printers due to factors I am not aware of.

Anyways this is getting long so I will end it here... any input or ideas or other manufacturer suggestions are very welcome... as you see I am sorta on a budget so I am trying to figure out if some of the cheaper options out there are not just duds for sale... hopefully give back to this community, which I love already given wheat I see, and how freely people exchange help and upgrade ideas. Glad to join you guys.

@jebus

My advice is that you build your Makerfarm i3v stock, without any mods, and use it as such for a few months, then check whether there is anything to gain at all by making any mods to it.

Just my $0.02...

I just finished building the I3V 12" unit. I am now getting prints that are measuring +/- 0.02 mm (0.0008 inches) from requested in PLA. I can't complain at all.

o yea my plan was to use it stock a while, i honestly wasn't expecting these things to get here that soon, most stuff I heard took 3 weeks... not 3 days to ship lol... but i totally get what your saying, until i get this thing calibrated and running right I am not going to start messing with anything