The buffer memory is, of course, good if you have the switch filled up. In theory it should help the Store 'n Forward a little.
The 1810G-24 is silent (No FAN), but the 2510G-24 is certainly not loud at about 40dB.
The 1810G-24 comes with an AC Power adapter; I hate those! The 2510G-24 probably comes with a typical power cord like its big brother the 2510-48.
1810G-24 supports only:
Network Time
Prioritization
Dot 1Q VLAN Tagging
Link Aggregation
LLDP (Finds connected switches)
It is nothing more than a packet pusher... Well a network frames pusher ;-)
2510G-24:
All the same stuff and more:
RADIUS/TACACS+
802.1X (Port based control. I.e. Dynamic VLAN assignment)
Full TFTP, Telnet, and CLI
SSH & SSL management
SNMP all versions
IGMP (Great for multicasting workstations)
Overall, if you have doubt, I recommend the 2510G. It is still a very inexpensive switch... cheaper than the 2810G-24. In the same price rage of the older 2626 10/100 stuff.
Essentially the 2510G is almost the same as a 2810G. Both are better than the 1810G in that they have more features.
If you are never going to do VLAN, and you do not want to setup RADIUS authentication or anything like Port Security, and/or are uncomfortable with CLI the 1810G is a great performer for the price.