Whether the guitar amp is tube or solid state, mic'ing the speaker is the standard way of getting the final product into the recording chain. So much for "tube warmth."
Direct from the amp's output, the signal tends to sound bright and spiky. First time I tried to DI an electric guitar for PA was the last, not acceptable. Since then some products came out that try to emulate the sound of a mic'd speaker, everything from H&K's "Red Box" to Rocktron's "Juice Squeezer" and another similar gadget from Groove Tube. All of 'em roll off top end, roll off low end, put a mid peak here or there, and the fancier ones add some compression/limiting. A couple of amp manufacturers put in DI outputs that have some degree of sonic treatment, usually just a low pass filter iow roll off the highs.
If possible audition the Amp/FX simulators you mention. No guarantee you'll decide to spend extra $$$ for one that actually has tubes. Whichever sounds best to you, get that one tubes or no. One advantage of the tube-free ones, you'll never have to wonder whether the tubes are failing.