My younger brother has Allied. He rolled his 2006 Dodge quad cab. They cut him a check for like $24k. He only paid $17k for it. They pay out based on comparables in the area, not on bluebook value. I'm bias with Allied simply because I know people that work for them and they are good reliable people. But I've heard Geico's claim service leaves a lot to be desired. All-State, State Farm, Farm Bureau, etc... I'm sure their claims service is good.
Just make sure you not only compare apples to apples in terms of coverage, but find out if their are introductory discounts that will fall off after your first term and find out what discounts become less over time (i.e. new vehicle discount). Also, ensure they ran a MVR on you as well since your current company will have already done so and adjusted the rates accordingly. When coverage is bound, the company has a 60 day discovery period and can jack your rates up within that time based on credit score information, clue report information (claims), MVR information, continuous coverage within the last year to 3 years, etc.
Rarely have I seen an online premium remain what it was when initially obtained.
Another thing to consider, how far away from the long term policy holder discount are you with Allied? Do you know what your premium will be after it takes affect?
Also, when you have been with the company for a good length of time it makes it a lot easier for the company to work with you if an exception needs to be made for whatever reason.
Anyway, hope this helps!