B2K w/ PDS is a great gun, i own one and you can see my hyping it up on these forums all over the place
yes, i think it's better than an ion for the same price, and i'll get into that later
first off...the gun looks great, it's comfortable to hold, and isn't too compact. One of my favorite parts about the gun is how it's stock delirin bolt is a quik strip...that means that it's easily removable, much like a spyder bolt is, if you've ever seen one of those work, it's a different system, but its handy like that.
Another great thing about this gun is that it's easy to use. The gun turns off/on with the flip of a switch, which might not sound like much, but it's easier than the ions system which involves this button that really doesn't push in
the same thing with the eyes. The switch for the eyes is right next to the on off switch and works the same way.
this gun is fast! it can cycle at 39, and shoots in the mid 20s. The ion is capped to 17 semi and 10 full auto.
it's stock barell is decent and it also has a easily removable feedneck which is handy
this gun isn't perfect tho....im gonna steal someone elses words here when i say that the stock hpr is worth more in scrap than a finished product. buy a new reg like a torpedo or a gladiator (my gladiator is coming soon

)
this brings up another point, it's easy to work on/upgrade
my main problem with the ion is it's too compact, to do something like clean the bolt, if you have a bad pball chop, you have to take off the whole body etc. also, i hear it's hard to buy new parts for
b2k has cocker threads and ion has impulse which is a little harder to find, but it's not really a problem...there i think i covered it all...idk tho
ion has stock ramping board...there if i missed anything i'll add later
all in all i pick b2k pds over ion, but it's totally opinion, my friend bought an ion and i didn't like it so i got a b2k and love it...so if you can test the guns but my suggestion if you cant test the guns is to just go to the b2k and nvr look back