Help me choose: Harbeth 30.2 or SHL5+ XD in a 10 x 13 feet room?

I'd also look at the Graham Audio equivalents - the primary benefit being they've been designed by Derek Hughes instead of Alan... And the signature editions if you can. 

@big_greg +1

I have owned every Harbeth minus the 40. I just sold the HL5 40th super plus with Tontrager stands and replaced them with the P3esrXD. In my size room ( 20x15) they are the only Harbeth that do  a  complete disappearing act like no other speaker  that I’ve owned including Spendor, Falcons, KEF, etc.! BTW, in my opinion the other Harbeths that you mention I would say that they are not a good fit for that size of the room that you will be putting  them in!!

Yeah, the two Harbeth models & REL subs mentioned are just too much for that smaller space. Honestly, get a set of KEF LS50 Meta and then maybe add the C62 wireless sub only after you've experienced the speakers in your room without it. It's an excellent combo and will be fabulous in your smallish room. If you feel that's too vanilla, a set of Opera Prima monitors and you may not need a sub at all; really great Italian smaller stand-mounts. So many options but what you've tossed out as considerations are overkill in a big way. If it's gotta be Harbeth, the P3ers XD is the match & add (1) small sub if you must. Just my opinion.

@yogiboy I sold my Super HL5 Plus 40th some time ago, preferring the C7s over those.  I've also owned Stirling Broadcast LS3/6, and no longer have those either.

I have owned P3ESR SE speakers for a few years, and have always kept those in a second system, thinking they were too small for the main system.  After hearing the Falcon LS3/5 2024 Limited Edition at a friend's house, I decided to try the P3ESRs in my main system.  My room is odd shaped and opens into my kitchen / dining room, but it's a fairly large space.  They sound fantastic in there and may not leave.  They are augmented by 4 subwoofers, so there's that.

I will say that the Falcon's were really amazing, providing much more detail than the Harbeths.  They were fun, but the Harbeths have plenty of detail and are so easy to listen to.

In that price range, I would also consider the Fyne Audio bookshelf speakers, particularly the F-701 and the F1-5.  I have the floor standing G-702s, and the sound quality is superb, and the two mentioned should be superb with a subwoofer(s).