Absolutely! It's a great value as it is with all the games you have access to and deals so for $40 it's awesome. I'm figuring that with the new generation (PS4) around the corner that the Plus prices might go up in the future so I think now is the time to buy since it will just add to your subscription.
Yeah I'm picking it up mostly for my vita though. It'll carry me into the PS4 era for a couple months too so not too shabby