I don't like L.G & Samsung because...
1) They don't have a good OS. But this is changing now as L.G is going to use Windows Mobile while Samsung is using Symbian & Windows Mobile.
2) They lack a PC connectivity software like Sony Ericsson PC suite or Nokia PC Suite. This isn't a problem with Windows Mobile phone though from these manufacturers.
The PC Suite for SE Phones is just crap.
When you connect in Phone Mode, there are only two options.
1) Synchronize
2) PC Settings
And in Data Transfer mode, you've got three options
1) Quicktime
2) Disk2Phone
3)Adobe Photosmart
And all these three again have to be installed separately.
I don't see any real use of it.....
But if you consider Nokia, There is so much you can do like image/video/music transfer, Backup the phone
Sync the contacts etc......
Never used LG/Samsung, neither do I know anyone who uses them... So can't comment about the connectivity options.