@AndrewHeath - It's about a 2-hour drive to the LeDong area from Sanya. Best (cheapest) bet would be to find some lodging in LeDong, as it's about 15km to the JianFengLing Gate. Otherwise there is the JienFeng Village which also has lodging, but is probably also primed for tourist-pricing.
Tickets to the reserve are 60kuai per person per day. It's a 15km drive up to the mountain peak (which requires a further 1.8 km climb up stairs to a viewing point that will likely be covered in clouds), and a 16km drive in the other direction to a lake. You could go a further 10km past the lake on a horrendously bumpy dirt road to reach some villas, but they're probably over-priced.
I visited there the past 2 days, but I drove my own vehicle, so I'm not sure about transport. I did see a number of 3-wheel motorcycles driving passengers up, but that's slow-going! I didn't see any buses inside the reserve, though there are a number of people who actually live inside. Depending on your connections or scheming abilities, you may be able to stand at the gate a bum a ride with someone. Perhaps try one of the green trucks of the locals?
I haven't posted any sightings on eBird yet, but I can tell you I saw the following (as well as a number of other birds more common to the island): Scarlet Minivet, Grey-chinned Minivet, Black-browed Barbet, Sultan Tit, and White-crowned Forktail.
FYI, I didn't see all these in the common tourist areas, but rather took a road less traveled where absolutely no one goes. Just keep your eyes peeled for pathways and such, and if you're really able to hitch a ride with a local, visit their farm. You're bound to see more birds wherever the tourists are few!
Good luck!