Buy it. It is a wonderful game.
The game is supposed to be difficult and unforgiving. It is not cheap though. The randomness has only gotten me cheap deaths a handful of times. They suck when they happen, but they are so rare that they don't become a problem for me.
I've dealt with a lot of randomness with the game, not always cheap but sometimes it is the case. The game expects you to die and learn from your mistakes, it's more of a trial and error game I guess. But even when you do eventually get used to it, you still get put in tricky situations that catch you off guard. One minute you think you're doing great, the next second you die easily and lose all that progress you've made.
After playing the mines section so many times, I finally made some good progress with the jungle levels and actually made it to the first ice level. The game's balance can also be off for its random levels (even though it's also a good thing), not sure if the jungle levels were pure luck or that they were less challenging.
I'm mixed about the game so far. It really seems like it's something unique, a game that isn't comparable to many games out there, it has an intriguing side to it, brilliant ideas with the way the game is designed, good controls and just wanting to play more of it.
But I'd have really liked it if it was a bit less stressful. I like challenging games (not cheap though), but I hate redoing sections over and over because the game doesn't give you a way to save your progress properly, this artificial length being extended with the way the game is designed instead of challenge. For instance, you have this character that creates shortcuts for you. Wonderful! But why do you have to donate him stuff, and why do you have to play the mine levels at least 3 times along with donating until a shortcut is complete? Why can't there be a shortcut the moment you finish a section?
I hope I'll get used to the game and enjoy it more, but I'm not looking forward to dying a lot.
There's a ton of tips... EsotericManiac had put together a guide on some of the more advanced stuff with pictures.
I guess it depends on how you play and your play style, but if you learn how to overcome whatever is currently killing you most of the time, you will do better. I was rusty when I first started playing again regularly, now I make it to the temple (or at least the ice caves) most of the time.
Yes, I learned to overcome certain obstacles, it's getting better but it's not enough.
Sometimes you have a lot of water in the jungle levels, there is a huge fish there along with tons of smaller fishes. How the hell do you deal with them?
I love it all! 
