If I didn't have a PM I'd probably give Stages a go. For me it didn't make any sense to get a stages as a second. I got such a good deal on my second SRM that when you consider that I'd have to buy a garmin for it (unless I have bad info I couldn't pair a PC7 with a stages) that it would have cost me almost as much to get a stages (second bike so I'd need the full crank).