Need to be careful about broad proclamations on either side of the BT latency spectrum here because APTX LL can have a delay as small as 30ms while regular SBC Standard BT can have a delay as large as 270ms (that's a quarter of a second, folks). I have tried BT headphones that are not APTX or APTX LL and the delay is intolerable when swinging with high recovery speed, to wiggle on the target , pinpoint, or when you have multiple targets under the coil (i.e., when swing speed is fast, when you are rapidly changing swing direction, or when there are targets within close proximity to each other). It drive me nuts. Depending on your swing speed it is like you are picking up two targets separated several inches from each other when there is only one target there.
While I believe you can get away with something that is not APTX LL, I think it is a stretch to say that regular BT does not have excessive latency (at least at the 270 ms end) and it is somewhat of a crap shoot as to whether you will be satisfied with non-APTX LL earbuds since the delay spec is hardly ever published for individual models, only whether they comply with certain general BT specification categories and those categories for the "standard" bluetooth categories can have a wide variation in the allowable delay times. The Bluetooth Latency Delay categories break down as follows:
APTX LL Delay = 30 - 40ms (these work great)
APTX Delay = 60 - 80ms (I have found a set of earbuds here that has tolerable delay)
BT AAC Delay = 90 - 150ms (I would be wary about getting something that might end up on the high side of this spec)
BT SBC Delay = 170 to 270ms (not sure these would be tolerable anywhere in this range).
You can go by word of mouth, anecdotal testemony that non-BT APTX LL work for others and may work for you but who knows how tight the manufacturer keeps the delay when it can vary by 50 to 100 ms from unit to unit. That is why I would look for APTX at least but could see getting away with BT AAC.
BTW - the Soundpeats mentioned earlier are APTX (like the Anker Soundcore Curve and similar Slim+ I mentioned previously), I believe, so they should be OK but only you can tell if they will work for you.
Finally, another alternative to BT earbuds, if you have a set of corded earbuds or headphones you love, is to get an APTX LL receiver or receiver/transmitter module into which you can plug your headphones. They are tiny, cost about as much as a set of earbuds (around $25 - $30) and you can just stuff it in your pocket or in a baggy or whatever to keep them out of the weather and use your wired headphones you love, yet remain untethered to the detector. Just another option.
Those that say their "Regular BT" headphones are working well without excessive lag, it would be helpful if you posted the model number so we can determine what category they fall into to see if we can ascertain the delay spec for the specific model and get a bead on what delay is tolerable rather than rolling the dice. Thanks.
HTH HH