BTD had a bad rep back in the Mix + days... And as a result many folks prefered to 'record back to PT' or to a recording device.
There have been some software revisions since..
Then HD came out,
It's hard to track detailed aspects of Digi software inprovements in the area of 'sonics' , and they aren't a company likely to say "look folks we improved this!" as it could be seen as an admission there was something wrong with it in the first place. BUT that said Digi DO tweak at things, sound quality being one of them, it just usually takes 400 + posts and a LOT of questions on the Digisign User Group to get to the bottom of exactly what's been improved...Engineers at Digidesign often don't feel they owe anyone detailed explinations
(this fuels Digi's Imperious reputation......
Im*pe"ri*ous (?), a. [L. imperiosus: cf. F. impérieux. See Imperial.]
1. Commanding; ascendant; imperial; lordly; majestic.
2. Haughly; arrogant; overbearing; as, an imperious tyrant; an imperious manner.
Syn. -- Dictatorial; haughty; domineering; overbearing; lordly; tyrannical; despotic; arrogant; imperative; authoritative; commanding; pressing. -- Imperious, Lordly, Domineering. One who is imperious exercises his authority in a manner highly offensive for its spirit and tone; one who is lordly assumes a lofty air in order to display his importance; one who is domineering gives orders in a way to make other feel their inferiority.)
+ no doub't there are some commercial business secrets wrapped up in their work.
So it's unsurprising that lingering doubt remains about the PT BTD issue on pre HD systems.
As for where HD BTD is at...... I lose track......