Pellet stoves

Personally I don't know if I would go for a pellet stove again. I had an Exraflame and I found it a lot of work.
The chute holds 1-2 bags of pellets, so you're forever lugging bags around. Pellets burn clean, but you still need to empty the ash every few days. You need to either spend a few thousand on a silo or you will have to get pellets once a week and throw them into the garage or the shed.
Every few weeks you need to take it apart and clean out the system. It's horrible and dirty and a lot of work.
At least twice a year, you need to clean the chimney. MAKE SURE that you have a chimney that can be easily swept. Mine wasn't and I cursed it to hell every time.
You will need a dust mask and a large capacity vacuum cleaner if you do it yourself.
Or you spend a lot of money on a technician to call out and service it and separately a chimney sweep.
The one I had was horrible at starting up, took 2-3 goes most of the time, that means opening it up, emptying the pellets again, waiting half an hour till it cools down again (even if it never lit).
Replacing the glow plug was not fun, but replacing the pellet feed motor was dreadful.
I'd go for a simple stove next time.

The aria doesn't look to bad to clean at first glance.
Mine also heated water and radiators, so was a lot more complex to clean.
To my mind a solid fuel stove would be a lot less complex, meaning less to go wrong, cost less in the first place and have a longer life expectancy.
Also, wood or coal for burning can be bought anywhere, but pellet stove burns only pellets.

It's the usual green insanity.
Wood burning from renewable forests = good because carbon neutral, what about all the other sh*t? Who cares.
Diesel = good because less CO2. What about all the other sh*t? Who cares.
Then start screaming and jumping up and down because inner cities start to resemble 19th century London with fumes and grime and "no one could have EVER foreseen that!"
Pellets is just another form of burning wood, but that's good, because it pellets, all modren and fancy, jaysis, it has to be good!
Greens are just the same as everyone else now, sell their mother for short term political gain, fcuk the consequences and don't think beyond the next election.

On a practical note.
Wood pellet stoves with a backboiler are a screaming nightmare to clean and maintain. I reckon (but don't know) that a room heater only, would have to be far easier to maintain. Maybe easier than a solid fuel stove (with lighting and daily cleaning), but you still have to take higher purchase price and maintenance into account and possibly higher fuel costs, I don't know about that one. But there's a convenience element to it.
As for storage. I used to go to the yard once a week and by 10 bags @ 15 kg each and feck them in the garage. I kept them on a pallet, a bit off the ground.
Dampness was never an issue. If your pellets go damp, they turn into weetabix and are no good anymore. And I would always take 2-3 bags with me from the garage and keep them beside the stove, far handier.
Don't bother with a pellet silo for a small room heater. It'll never pay for itself with the marginal difference in price. And you can buy pellets as needed, rather than having to buy 2 tons at a time. I would only buy a silo if I had to heat Dromoland Castle.
If there is an existing stove, I would stick with it, otherwise probably oil.

Finally, one of the biggest drawbacks of a pellet stove is that you cannot go on 2 weeks skiing holiday and throw on the timer. The pellets don't last more than a few days. So you gaff will be frozen unless a neighbour calls in and throws in a few pellets.
I now have gas central heating from a pipelin and I love it to bits. It's virtuall mainetance free. Chimney sweep only checls everythying every 2 years and says "yeah, it's grand".