We used both the Snuggle Nest and the Arms Reach cosleeper. I found the SN very nice for the first few weeks, especially while we got used to having a baby in bed with us to allay our fears of rolling over on him. We eventually put the SN into the Arms Reach cosleeper (which seemed so big when we first started using it) to give him a cozy little spot. We also sometimes used a rolled-up towel under the Nest to elevate it slightly (the newer version has a wedge for this--it's to reduce spitting up). We also used the Nest as a bassinet in the living room sometimes. Oh, and we were using it in a double bed with no problems. It just depends on how much you and your partner need to sprawl out.
I have a Pack n Play that was given to me. It is so much better constructed and easy to set up and break down than the cosleeper. I wanted to love the Arms Reach because I love the concept, but I did not find it to be a quality product. It also is not safe to use at cosleeping height once your baby can push up on all fours, which will happen sooner than you can imagine! You can use it in a portacrib/play yard set up just as you can the Pack n Play, but again, the latter is much easier to use.
I would say stick with your PnP bassinet and then you can use the portacrib setup as a naptime crib if you choose not to buy a regular crib (we did not as we knew we would be cosleeping). You can spend you money better than on the Arms Reach. I thought the Snuggle Nest was worth it (I did get mine for $20 from Craigslist, though! The cosleeper, too--in fact, I got almost everything from CL--give it a try).
Congrats and enjoy your pregnancy! :D