There is no really a breed better than others, it's all personal preferences and of course, each rabbit is different. They weren't bred for personality purpose like dogs, so the differences between breeds are more on a physical level. Nevertheless, it is said that lops are more laid-back than netherland dwarfs. I've had two males lops and they were actually mellower than my female netherland dwarf. Netherland dwarfs are told to be energetic, not always that friendly (I saw reported on several account that they bite more than a dwarf would). It is true of mine, she is not good with being handled either. In my case, it is also true that the female displayed more instinctive reactions (like digging or food guarding) even after the de-sexing but she's a lot smarter and more graceful than my two males ever were (but then again, she's a girl ^^). And both males were nightmares before the neutering - agressive, sex-crazed, spraying urine everywhere... They became great about 24hours after the operation though.
If you get a female, spaying is absolutely necessary if you don't want your rabbit dying of cancer after about 4 years, and I'm not even talking about the phantom pregnancies or the mastitis. For males, neutering is more a thing of convenience (as long as you don't attempt to bond him with another rabbit) but you will beg your vet to do it if your rabbit is anything like mine were - Tybalt, especially, was a monster from hell...
Giant breeds have shorter life span than smaller rabbits, their hearts tend to be weaker. Also, as it was said before, they need more space. Aside from that, they tend to be really laid back and make great pets.
I think going to a rescue and taking a look might be a good idea. You might just fall in love with one of the rabbits there or get a better idea about what you want. When I took home Aki, my netherland dwarf, she wasn't at all what I was looking for. I just fell in love with her because she had that smart spark in her eyes. And for all her skittishness, biting and general bitchiness, I think she will forever be my favorite. She's not half as pretty as my blue otter dwarf lop that everyone goes "aaaaw" over and not nearly as friendly, but she's clearly the rabbit of my life. I've had her for 6 years now ^^.
As Azerane said, the rescue also give you the possibility of having an already bonded, spayed / neutered pair which will spare you a lot of grief and cost you a lot less money than going over the whole process by yourself.
You can go see the breeder too, but I would be careful with a breeder who has a lot of different breeds and too many animals. If you decide to go there, pay really good attention to the animals, the general cleanliness, ask what the rabbits are fed and look for signs of mange. Of course, the rabbit should come with his vaccinations done.
Have fun!