My boys are just under 3 years apart and it's going really well. Some adjustments have had to be made, but it's pretty awesome.
I had DS1 when I was 35 and didn't really consider having a second until he was 2. DS1 made the adjustment to DS2 as a newborn pretty easily so it was actually easier at the beginning. Now that DS2 is moving around more and becoming more aware of *stuff* we're having issues with sharing and hitting/pushing, but nothing too bad. It's all something that I, as an only child, find fascinating.
Good luck with your decision.
My girls are 21 months apart. We were aiming for around 2 years and got very lucky when trying for #2!!! I was told by many that with them this close in age, the 1st 18 months are the hardest and I 100% agree. I had 2 in diapers for a while which actually was pretty easy considering everything. DD#1 potty trained at 2 years 9 months. Each month, life got easier. Each stage the baby went through helped - I was not able to nurse her so my DH was able to help with night feedings and night waking. Once #2 started sleeping through the night at 4 months - life got much easier and then again, when she started on table food and when she gave up the bottle at 11 months. By 18 months, it really was way easier. Both girls were in twin beds, older DD was totally potty trained, both slept through the night, nap schedule was the same. The hardest thing for me was when the baby was taking 2-3 naps a day and they were at the opposite time of day as DD#1's 1 nap. At 10 months, DD#2 dropped to one nap and it was at the same time (after lunch) as DD#1 - life was good - we could all leave the house at the same time.
Not sure why 18 months was the magically age but it was, like clockwork. I just think at that point the baby was able to do more playing on her own and she was walking and just a bit less needy.
The issues now at ages 7 (on Sunday) and 5 - the girls love each other and are the best of friends but they also fight over many things like siblings do and since they are so close in age and close grade wise in school (going into kindy and 1st), they compete over many things and even have friends that over-lap. I love that they can share clothes and toys as they are close in size and have similiar interests. We do work hard to do things 1:1 with them and make sure they make decisions on what they want and not just what their sister is doing/choosing.
I would not do it any other way - I was over the diapers and sleepless nights in a very short amount of time. I have friends who have kids 2.5 to 3.5 or more years apart and I just can't imagine that for me. I have never been a huge infant fan and was the same way with my kids - so happy to have gotten that part over and done with and now that the girls are older, we are doing so many fun things - and since they are so close in age, we can do that without either feeling like the activity is for babies or too old for them.