I've had my share of inexpensive scopes, and many of them have been satisfactory, only a few have been a waste of money. Most of the scopes manufactured today are pretty clear, and clarity tends to be comparable with many mid priced scopes. The quality of the scope should be considered based on how it will be used. Clearly a scope that can be purchased new for $150-$200 is not going to measure up to an expensive scope on a heavy recoiling rifle like a .378 Weatherby, it should not be counted on to stand up to rough handling in extreme climatic conditions over a long period of time, and it will be prone to failure if windage and elevation adjustment are frequently made, particularly if a lot of shooting is done at or near the limit of the adjustments. Conversely an inexpensive scope that is mounted on a rifle that produces mild recoil, that is not exposed to dramatic temperature changes or to temperature or humidity extremes, and is only infrequently adjusted after its initial zeroing, can provide reliable service almost indefinitely. I would be surprised if the combination of a .270 Vanguard topped with a 3-9X40 Redfield doesn't provide years of trouble free service, even in the miserable weather typical of the late fall in Canada.
The scopes to avoid are the ones that come as packages with inexpensive rifles. In such cases the rifle, the scope, and the mounts that hold the scope on the rifle are destined to let you down, even when used under favorable conditions. These things might not hold a zero, the turret adjustments might be hit and miss, anytime you take the scope outdoors on a cool humid day, it will fog up, they tend to have a short critical eye relief, particularly when set at high power which increases the likelihood of getting hit. The reticle might break under even with gentle handling, which is an unreasonable expectation for a big game scope in this country. If your rifle is going to be carried on a quad, a snowmobile, on horseback, in a boat, bounce around in a truck, taken on wilderness trips that exceed a day, or if the scope is mounted on a rifle that kicks harder than a .223, these things will fail.
As an aside, a fixed power scope can be a less expensive more robust scope compared to a variable. There are less moving parts in a fixed power, it needs fewer seals, and is usually smaller. A shorter eye piece can make mounting the fixed power scope with the correct eye relief easier than a variable which has a longer eyepiece, and variable eye relief across its power range. Keep in mid that the advantage of the scope is not its magnification, if it were we would all have 40X scopes on our hunting rifles. The advantage of the scope is that it places the aiming point and the target on the same focal plane, where iron sights and the target appear at 3 different distances, each requiring its own focus as the eye can only focus on one distance at a time. The purpose of magnification is to see the target. Big game is mostly easy to see, so there is little need for big magnification over normal hunting ranges.
