I'll have a need for Bulgarian Lev later in the year. I dont fly from LHR to bulgaria.

For 1100 Bulgarian Lev, ACE via BA wants £514.64 (which will include delivery after 1st feb). That would get me 2361 Avios max (1000 bonus, 514 via BA avios, 771 avios via BAPP cc card, 76 via world points)

ICIC bank wants £500.16, including delivery (via MSE FX checker)

So the extra £14.50 will get me 2361 avios. a good enough deal @ .61p a point, but not outstanding.
Note that without the bonus, it would be over 1p a point.

But you get much better value for more popular currencies and/or smaller amounts being collected. Also don't discount the added benefit of getting the spend up on your cc, for those that are trying to hit a spend limit.