My personal opinion
Well i brought a Stock ion for cheap off these forums, And since i dont plan to get any other marker.. ever (because Paintball for me at the moment is a bit on / off) I found it perfect, sure i needed to replace a few bits, but that was no trouble.
I have used it and I personally love it, Small, Discreet, Quiet, Accurate (With stock barrel, i have now uped it) and most of all in my case customisable.
II think with a PMR you look at it and say .. Hmm. a new Body, which maycost an Arm and a Leg, however any Ups for the ion (are you can Up virtually any component) Can be brought from Many retailers and off these forums for a low price, sure in the long-term you may spend a bit on it, but the way i am going, i earn that back quick, so therefore i Have a marker which i can make Mine and Mine only, which is what myself and many other users (Ion-crazy for example
) prefer. Customisability.
Please correct me if i am wrong, i have never used a PMR, but i have used other models up from it like the PM6 and i'm guessing that with a PMR, you get security, the knowing that the marker is going to perform at going to perform to a high standard Out of the Box. And as *blank* said above Tourneys are capped at 15-17 Bps anyway.
With the ion, it'll perform to a high standard but you have the options to tweak it to a standard or a point where you can say, "yup thats the way i like it".
If you are concerned with the Bolt out back weakness of the ion, this can be rectified in two ways, Buy a new Body and parts which accompany this design feature, or take a look at some of the new range markers also by smart parts like the ion-XE which has the Bolt out back feature, at roughly the same price of an ion, or mabe a vibe.
Personally i dont mind the effort needed to maintain the ion, because i think it is better to know you marker inside and out, how parts work what they do etc. SO if the worst happens, like a leak, you can identify the source and correct the problem.
Im not sure to what extent a PMR can be taken appart with reason ( i mean only in rare circumstances should you need to look deeper into the marker)
correct if im wrong.
Anyway Long as it is, thats my opinion.
cheers!
-Sugz