Help for Real-time PCR equipment choice - (Oct/13/2007 )

We're about to buy a new real-time PCR equipment (we already have an old Roche LightCycler). Our options are ABI StepOne/StepOne Plus, Eppendorf Realplex 4s, BioRad IQ5 and Stratagene MX 3005. I have some doubts:
Some of them use a tungsten lamp for exciting and other ones LEDS (Eppendorf). Does any have any experience about what's better? Same for detection, between CCD cameras or phtomultipliers.

In the case of ABI they've moved from fixed CCD detection on 7300/7500 series to a moving system that scans all 48/96 positions. Does anybody knows whether this kind of systems give problems of aligning, etc.?

Eppendorf realplex 4s has an amazing ramp rate of 6 ºC/s, is it useful?

All of them claims for freedom of choice for chemistry (Taq, probes, plastics, etc.) but in tha past that was not really true, specially in the case of ABI, does any have experience about this?

Finally, if we decide for ABI, our doubt is buying a StepOne Plus (96 wells) or two StepOne (48 wells) for more flexibility. What do you think?

As you see, we're in a mess so thank you very much to anyone that might help (it was easier when there only was 1 or 2 machines to pick out..).

I was deciding later this year about buying either ABI StepOne or Roche LightCycler480. No other companies were involved, because these two are the best (even if ABI doesn't thinks Roche is )and we wanted the best.

Sadly StepOne Plus came a week after we decided, otherwise we would purchase it. I like the system, it's new, it's cute and prize is great.

When diving into technical parameters, it's usualy better to get a gold standard. Very quick ramping rates may be interesting, but it could mean more optimizing, since standard protocols are different. About LEDs on the other side, I was told they last ages without replacing.

As for chemistry, I think lot of companies aim their product to work with major instruments manufacturer (ABgene for example has a complete scale) so I won't think it's a problem.

As for 48/96well format, definitely go for 96 if you decide for StepOnes. You will probably need it someday, we choose LC480 over StepOne mainly because of the 48well format. Just imagine you want to run standard curves with your samples, all in triplicates - 48 wells won't be enough.

(and finally, it's also important how the company behaves towards you, Roche representatives were always so helpful that it could be called annoying and ABI on the other hand always fought with bureaucracy, because they are such a big old company)

And as for other goods, I got a cute little magnetic bear from Roche and nice blue StepOne shirt and flashdisk from ABI, when they were struggling about me, so relax, choosing a real-time machine could be fun too

Thank you very much for your help. Finally we've accquired 2 Stratagene, mainly because they offered us an annoying price!