Curved and Straight Tonearms


Over the last 40 years I have owned 3 turntables. An entry level Dual from the '70's, a Denon DP-52F (which I still use in my office system) and a Rega P3-24 which I currently use in my main system. All of these turntables have had straight tonearms. I am planning on upgrading my Rega in the near future. Having started my research, I have noticed that some well reviewed turntables have curved 'arms. My question: What are the advantages/disadvantages of each, sonic or otherwise? Thanks for any input. 
ericsch
S arms are usually higher mass, often used with MC cartridges

"straight" arms with offset headshells which are not removable pretty much defines all the many good/great tone arms I've heard or owned.

For no tracking error, and no inner groove distortion, great mids and highs, very little wear to LP's - but with bass lacking weight get a Souther/Clearaudio and be done with it.
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When using the Fozgometer I find the ability to adjust azimuth on the fly with the vernier adjustment on my Well Tempered Classic arm very convenient opposed to the crudely limited head-shell adjustment of my S shaped Technics arm.
If the azimuth cannot be fixed by the limited headshell adjustment, you really need to return the cart you bought, you have a cartridge problem not a tonearm problem.
I read Robert Greene's review of the SL1200G in TAS last night.  I own an SL1200GAE and have done so for about a year now.  Of course, it has an "S" arm on it.  I also own a VPI Prime with straight tube arms (2) and have owned this TT for about 2 years.  I also own another VPI HW19 fitted with an SME Series III, another "S" shaped arm and have owned this one since 1989.  Anyway, if anyone is interested I will try and offer some additional perspective on the matters under discussion to the already excellent points made.