IMO yes the straight shafts alow you to get under objects further, easier, and with less bending. Also, IMO the straight shaft covers more area with less bending or reaching. I would take straight shaft over curved every time.

Only advanage I see with curved shaft don't have the 45 degree joint gears to wear out, but I have never had problem with gear joint. had one long enough to regrease, but the gears/bearing/housing inside looked very good for 7 years of use.

Original post is just what the mass market manufacturers wanted to hear. Twenty years ago, all of the cheaper trimmers were curved shaft, and all straight shaft were professional. The cheap guys (MTD, McCulloch, Homelite, Weedeater, etc.) then figured out how to make a straight shaft for a few dollars more. Now people think they're getting commercial when they buy straight shaft, but they are getting hosed.

Echo, Stihl, and Shindawa make high end curved shaft trimmer. Tanaka (TAS) and TMC also made high quality curved shaft trimmers, but TMC is straight shaft only now. The Tanaka TBC-225C is also the longest (52") curved shaft made. Price is about $180 vs $200 for TBC-225 straight shaft. Stihl also offered a long curved shaft.

Also, $90 to $130 won't get it done. That price point leaves you with cheap, mass market curved or straight shaft equipment. Either machine is basically a throw-away.

Pro quality curved shafts will cost you $180 and up. Next step is straight shaft, but with flexible drive shaft, about $25 to $50 more. These are good for trimming, but most manufacturers don't recommend using a blade. Top of line commercial will be straight shaft with solid steel drive shaft. Figure $250 to as much as $500.

As for gears wearing out in a straight-shaft, that won't happen if you maintain cirrectly. The pro straight shafts use hardened steel gears and ball bearings on the shafts. The cheap curved shaft machines only use a bushing, which needs even more maintenance (on a per hour basis) and will wear out even if lubricated.

Lastly, almost all trimmer engines rotate the same way, so a curved shaft will rotate clockwise at the trim head (looking down from above), while a geared head rotates CCW. Not a big deal, but some people have trouble going back and forth from one machine to another due to rotation differences. I think Tanaka was the only curved shaft to have engine rotate opposite so their curved shaft head spun same as their straight-shafts.

Rather concise overview GG . :)