JD, this is a good analysis and also a good idea for here as both are basically the two pre-eminent busty EE independent SPs for FBSM operating out of East London at the moment (and roughly same price).
Unlike yourself, I've seen Lora maybe around four times and Rasa just the twice.
Facially - I think it's fair to say that Rasa is attractive and takes care of herself whereas Lora is somewhat plain (but by no means ugly), some blokes may also prefer brunettes
Chebs and figure - Rasa is more svelte, agreed, Lora is also tall for a bird I think but more solid. Lora's chebs are just meaty as fuck.
HR and HE - Rasa is not particularly skilled in this direction, whereas I think Lora probably prides herself on her craft
Nakedity - although stipulated as naturist massage, Rasa only got topless and I was fine with this and didn't expect anymore for 40 quid all in. I've not asked Lora to go beyond topless and, I don't know why, tbh I am not interested in seeing her naked. I think one time she did hike her leggings down a little but I was too busy slurping on the chebs. I suspect I'd enjoy Rasa more naked but as you say, a woman working in a busy shop doesn't exactly exude confidence on that score.
YMMV - both sessions with Rasa were identical and I figured it's a vanilla service for which I was content for the price. Lora on the other hand, does seem to vary on mood.
Conversation - as mentioned, Rasa seems to have a set routine of bombarding the customer with chat and comments and tuts when you try to engage in prolongued cheb worship. That said, even after the events she was still going on and on until I'd pretty much left, particularly about why the shower wasn't working well etc. I can honestly say I've barely exchanged two words with Lora beyond the services and cost, after the event she seems to go to wash her hands and by the time she's returned I'm clothed and ready to leave, in fact once I had to leave the room to get her so I could hand her the cash.
Summary - both are effective, reasonably priced and blessed with chebs. Though I dread to think at the idiocy both must have to contend with from clients or even just prospective clients determined to push boundaries.
Which do I prefer for next time? - it always comes down to availability and my location as visiting their respective areas depends on either work or my willingness to schlep. There's been several times I could have seen Lora but instead elected to engage in tons of RO with Lauren a short walk away.