I have a slightly smaller unit (SB-23B <22.5cc version>), but I love mine. No gas leaks so far, and I've had it more than a year.
Don't have the guard catching on turf issue much (tall weeds/vines, but that's to be expected IMHO; top down helps solve this). Otherwise my height (6-4) might help prevent this in general in my case. YMMV.
Overall, it does a great job with the string trimmer. Nice and light too, but the smaller engine helps with that.
Can't comment on hedge trimmer attachment, as I don't have it.
If you haven't purchased anything yet, you might want to see if you can demo one (they had a 5 day test drive and no hassle return if not liked when I got mine).
If not too late, I hope this helps.