I think saying "diet and exercise" really is meaningless unless you describe what that even means (@JaredBusch did though, I'm just saying when people say that in general), and I hate tracking things, I really despise any extra effort; I am truly lazy. So, here's my story.
I got up to 375lbs and just did Atkins, didn't even bother exercising until after I lost the weight. Atkins works if you stick to it and continue to essentially stick to low-carb (under 50g of carbs per day for me) for good, eat a lot of fat (especially saturated), etc. I've never been more healthy, had better blood pressure, etc.
I did notice the biggest thing was getting off the sugar soda, switched to diet, and I found that I liked Diet Mountaindew the most, it seemed to taste most like the regular, plus sugar free redbull as well, which does have like 3g of carbs though.
The hardest was avoiding bread since I'm just completely in love with pizza, so I have it every once in a while. The second hardest was drinking enough water, 4 litres a day, which was hard at first but got easier.
I don't worry about salt or anything either, especially since I drink a lot of water. I hate lettuce, so I eat spinach instead, but I still have a hard time with vegetables in general.
What I liked was that so much protein allowed me to gain some muscle too whilst doing nothing, it was kinda weird, though I do have a genetic predisposition to muscle gain, and most people don't have this. Though most people who stay on Atkins or some form of it tend to report at least some muscle gain.
My main problem is that I've got a gene for overeating*, i.e. not being able to realise that I'm full. High fat helps a lot with this and also usually what I do is figure out how much I want to eat and just cut that amount in half, seems to work ok, no measuring or any BS like that. Fat doesn't make you fat, though most Americans seem to think so, but then again if what you ate directly correlated to what was in your body, then I guess I got a lot of bacon and hamburgers in my arms **.
*I had my genes analysed that's how I know this.
**I feel a lot of guilt about not keeping kosher, but I just eat bacon, no other pork products
In the end it doesn't matter what sort of diet or surgery you get if you don't change your life style. Plus also when it comes to exercise, stuff like running and walking doesn't really burn many calories. In fact, human beings are so efficient at running that we burn like 150 calories per mile, which is garbage.
If you want to ramp up weight loss, what eats fat more than anything else, is muscles. Lift weights, free weights, just get some crappy ones from a yard sale or something, don't waste money when you don't to.
Plenty of people get the surgery and just gain it all back slowly, because they go back to eating carbohydrates, and that's something to consider if you're genetically inclined toward type 2 diabetes (like me, and possibly you too), that your body will basically convert all sugars (carbs included) into fat, and counting calories will only work if you're running on like 700 calories a day for you, it certainly didn't work for me and was pure hell. Counting calories does work for about 25% of people though, so it may work for you.
I feel awesome. I lift weights like I used to in college and now I'm getting more attention from the ladies, and a few dudes too, but hey, a complement is a complement. My wife is still on my ass about vegetables though.
Just gotta stick to it.