It depends on your price predictions. If you see bitcoin hitting $500 this year, you may be better off mining, as your "profit" per month would improve significantly with the price. Difficulty will trail price by several months, there just isn't the capacity to host that many more miners. So you'd mine almost as many as in the $275 scenario, but get to keep more each month.
Right now, your margin is only about 50%. At $500, it would be 70%. (Although difficulty would pick up to eat away at that.)
But there are a lot of factors to consider. If the $500 rise comes in the last two weeks of the 12 month year, then no, it won't have made sense. If it comes earlier in the year, then yes it would have.
If the price drops to $100, you own a very expensive paper weight.
It isn't as simple as "buy and hold" BTC, but honestly, until the price is above $300, I would say "Buy and hold" is the safer strategy.
If the price stays steady here, then no, it is hard to justify.
Your factors are:
1) Current Price
2) Future price
3) Rate of change towards future price
4) Difficulty (from the perspective of technological innovation)
5) Rate of change of difficulty to react to future price (demand for new miners)
6) Hosting costs
7) Cost of equipment
Rate of change of hosting and equipment with future price (When profits were through the roof in late 2013, hosting was 25 cents/kwh due to lack of space and heavy demand)
Also, a big factor is whether you consider hosting a "sunk cost" upfront or a reoccurring monthly cost, that will affect your numbers as well.
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