I'm sure you know this, but for a fraction of that cost you'll get a green top grade coffee bean. Roast it yourself so it's always fresh. You won't look back. I've tried robusta. It looks amazing but is deadly strong and tastes like burning tyres.

I've roasted a few times, simply using an old hot air popcorn popper. It was a lot of fun, but there isn't anywhere local I can get good green beans. Do you have any recommendations for on-line shops?

Regarding robusta- first crack tends to be hard to hear, which can mess up your roast if you aren't careful. My subjective recommendation is to use them for ~10% of your total bean bill. Crema for days when you pull shots, great earthy flavor. Pairs really well with Sumatran beans.

Thanks - I'll try again. I'm probably not much use to you as I'm in NZ. I just went around asking at places that said that they roast it. I got funny looks but everyone untried sold me green beans. Eventually I got far back enough in the chain to find the supplier that everyone buys from. The defensive attitude goes away when they know it's for home use, not potentential competitor. The supplier have a taster employed and a list of about 50 coffees that I can buy. The taster is an excellent source of knowledge that can always recommend something new and great.

http://johnburton.co.nz

Tldr: ask your local roaster for some or ask who their supplier is.

sweetmarias.com

They have in depth reviews of all coffees. I've bought from them for years.

Thanks!

One suggestion: skip the hot air and use a stovetop popcorn popper. Both the air popcorn poppers and specific air coffee roasters struggle to get hot enough in my experience.

I'll give that a shot next time. Thanks for the suggestion!