I have been using all the Stihl head attachments with all my FS250R's with ZERO issues for some three years. Funny thing I have all these extra attachments from old FS90's & FS130 4-mix power heads around

, that have blown up or broke down over the years.
The 4-mix FS130's are not their yet in the power & torque vs a "true" 2-stroke, per (engine CC) in the same class,overall 4-mix reliability is still an issue for me. if you leave the guards on the FS130 will do fine. I remove all my trimmer head guards, and run extend line out, the FS250R swings the extra line with ease.
In defense of Stihl i have went through or "wore out" Shindy & Red-Max line trimmer's quickly too. Nothing equals the FS250R at 40.2CC & 13.0 lbs in the same class "heavy duty" line trimmers.
For me the FS250R is highly productive & bulletproof, and for that worth the money at $499 out the door and you will never be lacking power/torque. At 13.0 lbs it might be heavy, but a FS140 4-Mix unit is right their at 12.3 lbs in weight too. The FS250R does serve's as our "everyday weedeater's, and does not require going back to the trailer to get something larger in the thick or lush grass, or for right or way trimming either.
If you want something that will cut the big stuff with out any problems the
Fs 250 is perferct. As for the attachments question. According to the Stihl rep. that I spoke to he said that you could not run attachements on the 250 because of the gear heads on the attachments. The 250 has a larger shaft in it than the rest of Stihl trimmers which would not allow the attachment to work properly. I have had a 250 for several years and love it. Its a power house. I bought a FS 90 to run my attachment's on. I can't speak for the 130 because Ive never used one.