We are currently riding a Co- Motion Speedster with a FSA Gossamer crankset. I have replaced the BB once and now, we are currently touring, the BB is in need of replacing again. The first replacement was a rebuild using Phil Wood bearings. I did notice the crank shaft was a bit worn at that time. So my question is should I consider a new crank set up with a cartridge BB? Would this be a more durable set up? We will be back home in a few days and I will then pull the crank and inspect it. But thought I would get some advice!
Thanks!!

Is your current crankset square taper or ?

No, it is a FSA MegaExpo.

We have the same crankset on the rear and have had no problems and have not needed to replace any bearings.
I have had to replace bearings on our wheels several times.
I am not sure what you mean by: "new crank set up with a cartridge BB".
FSA MegaExo already uses cartridge bearings.

The FSA uses outboard mounted BB. It is a BB-7000.

I've had very good results with Enduro bearings in FSA Gossamer cranks on solo bikes so they are worth a try. If you are concerned about crank spindle wear, an added plus is that Enduro sizes the ID of their bearings for Shimano and RaceFace cranks which are a hair smaller than FSA so they are a very tight fight on unworn FSA cranks.

Thanks! I will check those out.